SOLUTION: Given:f(x)=4x-8 I need the steps, wrote in standard inverse notation.

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Question 1167517: Given:f(x)=4x-8 I need the steps, wrote in standard inverse notation.
Found 2 solutions by solver91311, greenestamps:
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


Replace with .

Exchange places with and

Solve for in terms of

Replace with

John

My calculator said it, I believe it, that settles it


I > Ø

Answer by greenestamps(13200) About Me  (Show Source):
You can put this solution on YOUR website!


Here is a formal process for finding the inverse, based on the idea that switching x and y gives the inverse.

(1) Replace f(x) with y and then switch the x and y to get x+=+4y-8

(2) Solve for the new y:

x+=+4y-8
4y+=+x%2B8
y+=+%28x%2B8%29%2F4

ANSWER: f%5E%28-1%29%28x%29+=+%28x%2B8%29%2F4

That is a standard process for finding the inverse; you should know and understand it.

For many relatively simple functions, you can find the inverse much more quickly by using the idea that the inverse function "un-does" what the function does -- that is, it "gets you back where you started".

In this example, the given function does this to the input: (1) multiply by 4; (2) subtract 8.

The inverse function, to get you back where you started, needs to perform the opposite operations in the opposite order: (1) add 8; (2) divide by 4.

That gives you the inverse function: y+=+%28x%2B8%29%2F4